STAR 62 GeV CuCu Event totals (as of 3/16/05, noon )

• Total: 12.830 Mevts of BBC Narrow• Goal > 20 Mevts. • BBC Narrow Trigger has been operational for 6 full days. The “run” average number of mb events per day is ~ 1.9 Mevts/day (N.B. Evts taken today not included).

Ave/day ~ 1.9 Mevts

STAR 62 GeV CuCu Event totals (as of 3/16/05, noon )

• Total: 11.618 Mevts of ZDC Narrow• Goal > 20 Mevts. • ZDC Narrow Trigger has been operational for 5 full days. The “run” average number of ZDC events per day is ~ 2.04 Mevts/day (N.B. Evts taken today not included).

Ave/day ~ 2.04 Mevts

62 GeV CuCu DAQ Hours

DAQ HoursTotal 3/10 through 3/15 (6 days) = 56.06 hrs

<DAQ hrs/day> ~ 9.3 hrs/dayN.B. “DAQ hrs” only count time when production Cu62 Production Configuration is running.

N.B. Hours today (partial 7th day) not included in numbers above.

22 GeV CuCu DevelopmentOverall Environment (Large backgrounds)

BBC Coin.ZDC Coin.BCC Yellow back.BBC Blue back.

ZDC EastZDC WestZDC Coin.

BBC Coin.ZDC Coin.BCC Yellow back.BBC Blue back.

Typical 62 GeV Backgrounds

22 GeV CuCu Development

Vertex Distributions for Data taken at 4:20 pm.

The Trigger was zdc-tacs

(ZDC coin. where each ZDC also has a valid timing signal (additional disc. thres,.))

Expected to have substantial impact parameter bias, but minimal collision vertex bias.

Short run with low statistics.

<Vz> ~ 10.6 cm, rms ~ 80.5 cm

<Vx> ~ -3 mm, rms ~ 5.7 mm

<Vy> ~ 1.8 mm, rms ~ 4.7 mm

22 GeV CuCu Development

Vertex Distributions for Data taken from 5:28 to 5:58 pm.

The Trigger was:

zdc (Just zdc adc coin.)

zdc-tacs (Add TAC disc. Thres.)

bbc-narrow (bbc coin. + timing cut)

N.B. Though I widened the timing cuts on the bbc (triggers mostly background without cut), the Vz dist. Is biased by this trigger)

<Vz> ~ 15.1 cm, rms ~ 72.8 cm<Vx> ~ -2.7 mm, rms ~ 5.3 mm<Vy> ~ 1.9 mm, rms ~ 5.4 mm

22 GeV CuCu Development

Vertex Distributions for Data taken from 4:42 to 4:54 pm.

The Trigger was:

zdc (Just zdc adc coin.)

zdc-tacs (Add TAC disc. Thres.)

bbc-narrow (bbc coin. + timing cut)

<Vz> ~ 18.1 cm, rms ~ 70.2 cm

<Vx> ~ -2.7 mm, rms ~ 5.4 mm

<Vy> ~ 1.7 mm, rms ~ 5.9 mm

I changed the bbc timing cut (widened it) between this run and 5:28 pm run.

Typical 62 GeV CuCu Vertex Distributions

Vertex Distributions for Data taken Tuesday from 9:00 to 9:20 am.

Running a mix of Triggers.

<Vz> ~ 4.4 cm, rms ~ 49 cm

<Vx> ~ -2.2 mm, rms ~ 3.6 mm

<Vy> ~ 1.8 mm, rms ~ 3.6 mm

N.B. This Trigger mix biases the Vz distribution.

CTB ADC Sum (Mult.)

CTB ADC Sum (Mult.)

BBC - Narrow Triggered evts

Same evts with ZDC coin. Req.

Ratio of Red hist. To black hist. above

Preliminary Conclusions:

• ZDC coin. Has very low efficiency for central CuCu collisions at 22 GeV.

• Including info. from ZDC triggered data set, the BBC has poor efficiency for peripheral collisions.

Pictorially (rough idea):For Central EventsSeen by BBCSeen by ZDC

For Peripheral Events